Electrolytic cell



E. soRENsEN 2,104,677 ELECTROLYTICKCELL 'Filed oct. 1, 1935 3sheets-sheet 1 Jan. 4, 1938.

Jan. 4, 1938. E. soRENsEN ELECTROLYTIC CELL Filed oct. 1, 1955 3Sheets-Sheet 2 INVENTOR ATTORNEYS E. SORENSEN ELECTROLYTIC CELL Jan. 4,1938.

3 Sheets-Sheet 3 Filed OC.. l, 1935 4M vv/ INVENTOR .QW Ww ATTORNEYSatented Jan. 4, 1938 UNITED STAT-Es 'PAraNT or-FICE ELECTBOLYTIC CELLEinar Sorensen, Rumiord, Maine, assigner to Oxford Paper Company, acorporation of Application october 1, 1935, sei-iai No. 43,021

'is claims. (ci. zar-ssi This invention relates to electrolytic cellsfor Vproducing chlorine and sodiumhydroxide from brine. Such a cell isdisclosed in my prior Patent #1,613,966, issued January il, 1927. 'I'hecell of the present application, in generaivconstruction and operation,is similarto theceil of my prior patent, but embodies certainimprovements hereinafter described and claimed.

The cell disclosed in the above-mentioned patent comprises a casinghaving a longitudinal partition which divides the cell into adecomposing compartment and an oxidizing compartment. Brine, to betreated, enters the decom.

posing compartment, the iioor .of which is covered with a slowly movinglayer of mercury which constitutes a cathode. Graphite/ plates locatedabove the mercury constitute theanode.

Electric current passing between the graphite notched graphite plates.yMeasured quantitiesv g of water are fed into the oxidizing compartment.

By the electrolytic action set up in the oxidizing compartment theamalgam is decomposed and the sodium reacts with the water to formsodium hydroxide solution. The mercury thus freed of its sodium thenentersY a pump chamber in which a rotary pump lifts the mercury andreturns it to the decomposing compartment.

The principal object of the present invention is to improve ytheoperationand increase the eciency of the cell just described byimproving certain of its structural details and by the addition ofcertain new features.

Considering the improved 'details and the new features more specificallythe objects ofthe invention are to improve and facilitate the flow ofthe mercury through the decomposing compartment; to improve the meansfor conducting lcurrent to the mercury in the decomposing compartment;to provide a mercury seal where the l.

mercury passes from the decomposing compartment into the oxidizingcompartment to prevent the entrance of brine into the oxidizingcompartment and to provide means at this point lfor spending thevelocity of the mercury before it' enters this seal; to improve thesystem of introducing water into the oxidizing compartment; and toprovide a mercury seal at the point where the mercury passes into thedecomposing compartment to prevent the 'entrainment of water by themercury as it passes into the decomposing compartment.

Other objects not specifically mentioned above will appear from thefollowing description.

The improved cell is shown in the accompanying drawings in which Figure1 is aplan view of the cell with the cover and the anode assembly of thedecomposing compartment removed to expose to view the interiorconstruction of this compartment;

Fig. 2 is a longitudinal section through the decomposing compartmenttaken on the line 2 2 of Fig. 1. In this view the cover and the anodeassembly are in place;

Fig. 3 is a longitudinal section through the oxidizing compartment takenon the line 3 3 of Fig. 1;

Fig. i is a detailed sectional view of one end of theoxidizlngcompartment taken on the line 4 4 of Fig.' 1; I

on the line 5 5 of Fig. l;

Y Fig. 6 is a transverse section line 6 6 of Flgri; I

Fig. I is a transverse section taken just to the rear of the section ofFig. 6, i. e., on the line 1.-1 of Fig. 1';

' Fig. 8 is a transverse section taken just to the rear of the sectionof Fig. '1, i. e.,v on the line 8 8 of Fig. 1, l and Fig. 9 is-atransverse section taken on line 9 9 of Fig. 1.

The improved cell has an external metal casing I which is generallyrectangular in shape as shown in'Fi'g. 1. Itis divided into twocompartments by a'longitudinal partition 2. One of these compartments,designated 3, is the decomtaken on the the posing compartment and theother one designated I is the oxidizing compartment. As best ThemercuryV enters the decomposing compartment 'from the oxidizingcompartment at 8. The

" mercury passes in a thin layer over the bottom ai the decomposingcompartment in the manner lto be hereinafter described and is dischargedf 20- Fig. 5 is a sectional view similar to Fig. 4 taken passes throughthe decomposing compartment it,v

forms an amalgam with the sodium of the brine, and the spent brinetogether with the liberated chlorine is discharged through an outlet illocated at the proper elevation to maintain the desired depth of brinewithin the decomposing compartment.

In the oxidizing cell the mercury amalgam passes over the notchedgraphite plates Measured quantities of water are fed into thiscompartment by means to be hereinafter described to maintain in thiscompartment a pre-1 determined densityand to compensate for the waterconsumed in the displacement action. The displacementy action whichtakes place in this cell frees the amalgam of its sodium and causes thesodium to unite with the water to form sodium hydroxide solution. Thesodium hydroxide solution is withdrawn from the oxidizing compartmentthrough a pipe i3 (Figs. l and 9) which discharges into the lower end ofreceptacle it. This receptacle has a vertical partition i5 dividing itinto two compartments. The sodium hydroxide solution enters the bottomof the right hand compartment (as viewed in Fig. 1) and flows over theupper edge of the partition i5 into the left hand compartment. it isthem` discharged through an outlet pipe i6 in the bottom of the lefthand compartment. In the right hand compartment there may be located a.hydrometer il (Fig. 9) by which the density of the sodium hydroxidesolution may be measured. The level of the sodium hydroxide solution inthe oxidizing compartment is determined by the elevation of the upperedge of the partition i5. Therefore, the level of the sodium hydroxidesolution in the oxidizing compartment may be varied, if desired, byraising or lowering the receptacle i4 and thereby raising or loweringthe elevation of the upper edge of the partition I5. This may beeffected by providing the pipe I3 with a removable section i8 which maybe replaced by a longer or shorter section.

The mercury freed of its sodium passes into a pump well i9. A rotarypump 20 lifts the mercury from the well `and discharges it at a higherelevation where it iiows into the passage 8 of the decomposingcompartment thereby completing the cycle. The pump hasa series ofperipheral pockets 2| (Fig. 6) to which the mercury is admitted throughperipheral kopenings 22. It is discharged from these pockets throughopenings 23 (Figs. 7 and 8) in the lateralwall of the pump. It is thencaught in the manner hereinafter to be described and passed on to thedecomposing compartment. The mercury pump is operated by a sprocketwheel 24 connected by means of a chain 25 (Fig. 6) to a sprocket wheel26 (Fig.

mounted on a horizontal shaft 34 to the outer end of which is connectedan arm 35. This arm is engaged and deiiected by a projection 36associated with the sprocket wheel 24 so that every time the sprocketwheel makes one revolution the pipe 3@ is lifted to scoop up a smallportion of water and dump it inthe compartment 33. From the compartment33 the water passes through a pipe 3l' directly into the pump well I9.picks up both the mercury and thevwater and the manner in which thewater and mercury are separated so that the water is delivered tooxidizing compartment and the mercury delivered to the decomposingcompartment will be hereinafter described.

As thus far described the electrolytic cell is substantially the same inconstruction and operation as the cell disclosed in my prior patentabove referred to with the exception that in the cell of the priorDpatent the water, after being scooped up by the oscillating pipe, isdelivered directly intothe oxidizing compartmenh'whereas in the improvedcell of this application the water is delivered into thewell of themercury pump. The differences in construction and operation whichcharacterize the improved cell will now be described.

The container or casing l may be made of any suitable metal but it ispreferablymade of steel. The use of steel instead of cast iron greatlyreduces its cost. Convenient and inexpensive manufacture is madepossible by maintaining straight lines throughout its construction. Thecasing is shaped to conform with the mercury iiow arrangement.

A three point supportwis used for the cell in order to maintain evenbearing and to facilitate releveling of the cell should this becomenecessary. The three supports are shown at 31, 38 and 39 in Figs. 2, 3and 9. As best shown in Fig. 9 each support comprises a hemisphere 40,preferably made of metal, the-flat side of which is secured to thebottom of the casing i and the curved surface of which rests in theopening 4l of a metallic member 42 which' might conveniently be a pipeange. The member 42 rests on continuous, undivided flow of a uniformlythin` layer of mercury through the compartment at a suitable distancefrom the anodes and in con- The pump formity with their area. The floorof the decomposing compartment is divided into three adjacent channels45, 46, and 41 (Fig. 1) by apair of longitudinally extending ribs 48 and49. These ribs may be molded from the concrete which lines the casing ofthe decomposing compartment, as best shown in Figs. 7V, 8, and 9. -Theoutermost channel 45 communicates with the transverse passage 8 throughwhich the mercury enters the decomposing compartment.- 'I'he channels 45and 46 l communicate with each other at the right hand end of the cell,as viewed in Fig. l, and the channels 46 and 4l communicate with eachother at the left hand of the cell, as viewed in this gure. 'I'he righthand end of the channel 41 ment. The mercury, therefore, follows atortuous passage as follows: From the entrance passage 8 it passes tothe right (as viewed in Fig. 1) through the channel 45, then to the leftthrough channel d6, and then to the right through channel 41 and is thenconducted by the passage 9 into the oxidizing compartment. 'Ihe floorsof the channels 55, t5, and .41 are level in both directions whichnecessitates .a slight head of mercury at the inlet of the first channelin order to obtain a flow of mercury through the compartment. By usinglevel instead of pitched floors the amount of mercury which it isnecessary to use may be greatly decreased and still maintain iidw of acontinuous undivided and uniformly thin layer of mercury through thecombined lengths of the channels.

By reference to Figs. '1, 8, and 9 it will be seen that the channel 46is at a lower level than the channel 45, and the channel 61 is at alower level than the channel- 46. At the right hand end of the channel45 (as viewed in Fig. 1) there is a step or drop 50 where the mercuryand amalgam cascades to thelevelof the middle channel t6. There is asimilar drop I at the left hand end of channel 66 where the mercury andamalgam cascade to the level of channel d1. A third drop 52 is locatedat the right hand end of channel 41 where the mercury and amalgamcascade to the level of the passage 9. These steps, or drops, facilitatethe iiow of the mercury and decrease the total amo t of mercurynecessary for operation of the cell. They also cause an eicient mixingof the amalgam with the free mercury. This mixing of the amalgam and thefree mercury is further promoted bythe change in direction of ow aspthemercury and amalgam vpass from one channel to the next.

lIt will be noted that the mercury is not subdivided at the entrance endof the decomposing compartment into several parallel streams which flowin the same direction through the decomposing compartment as in the celldisclosed in my prior patent, but there is None undivided stream whichfollows a tortuous path through the decomposing compartment.n This makesit possible to eliminate the dams which have sometimes been foundnecessary at the outletsy of the channels when the mercury is subdividedand flows through the channels in the same direction. 'When the mercuryis thus divided between a plurality of "channels the mercuryl hasinsufficient iiow through any one of the channels to maintain a uniformand continuous layer of mercury over the channel floors unless dams areused. Moreover, the iow of the vmercury in that typeof cell is notpositive in action because deposition of graphite and other impuritiescause scum forma tion at the inlets to the channels thus causing unevendistribution of the mercury between the channels and this results in toomuch mercury flow through certain channels while too little flowsthrough others. Positive and uniform flow of the mercury is obtained bythe channels communioating in series rather than in parallel. In

the improved cell herein disclosed the rate of iow i of the mercurythrough the decomposing compartment. is controlled by the amount inexcess of that necessary -to cover the oor of the channels of thedecomposing compartment and the slotted graphite plates of the oxidizingcompartment. l

The anodes do not rest uponprojections onthe floor of the decomposingcompartment as in the cell of my prior patent, but are rigidly fastenedto, and suspended from, kthe cover of the decom- `posing compartment andform a unit therewith. 'Ihe cover of theY decomposing compartment isshown at 53 (Fig. 2). It may be made of light material, such asimpregnated fibre. Inasmuch as' the cover is called upon to support theanodes, it is preferably reinforced by transversely extending angleirons 54 and longitudinally extending angle irons 55. The cover 53 issupported at its edges on the concrete walls of the cell by means ofiibre strips 5B. As the anodes wear down, the bre strips 56 may beremoved one at a time, thus lowering the anodes and restoring the properspacing between them and the mercury cathode. Each graphite anode I0 isrigidly secured to the cover 53 by a graphite lead 51 threaded at bothends. The lower end of the lead 51 is screwed end of the lead passesthrough an opening in the cover 53 and is clamped to the cover by a brenut 59. In the particular cell shown in the drawings there are threeanode plates in each channel thus making nine all together.. The threeanode plates of each traverse row are electrically connected bymeans ofa metallic conducting strip VSil (Figs. 2 and 9) which is secured to thegraphite leads 51 by means -of stud bolts 6i. Three bus bars 62 conductcurrent to the three traverse rows of anodes.

The cover and anode assembly may be easily removed as a unit when it isdesired to clean the cell. The cover is much lighter than the concretecovers heretofore used thus facilitating its container and are securedto the bus bar 54 by means of nuts 66h. Over each metal bar B3 theconcrete oor is provided with-a series of holes 65 by means of which themercury makes contact with the bar. The path of the current isthereforefrom the bus bar 6B tothe bolts 55a, to the transverse bars 83,then to the mercury cathode,

through the brine to the graphite anodes I0, then through the leads 51and connecting strips 60 to the bus bars 62.

The improved brine inlet comprises a hard rubber pipe 66 (Fig. 2) havingan elbow 51 which supports a piece' of glass tubing 6B in a verticalposition. The glass tube extends upwardly to a point above the level ofthe brine in the decomposing compartment. Brine is fedcontinuously intothe glass tube 58 by a small 'glass pipe 69 lcommunicatingwith the brinesupply pipe.` This arrangement serves the purpose of sealing the brineinlet thus preventing air from .entering the cell. It also minimizeselectric current leakage as the brine is caused to fall through the airfor a short distance fin a somewhat dispersed column partment it formsa-seal and thereby preventsy io as it leaves the discharge end of thesmallglass y brine from passing from the decomposing compartment to theoxidizing compartment. This seal is therefore called the "brine sealfand is constructed as follows: At the right hand end of the oxidizingcompartment 4 (as viewed in Fig. 1) there is a pit or well 1U molded inthe concrete lining. In pian View this well is relatively narrowlongitudinally of the cell and is relatively long transversely of thecell. The bottom of the well is tapered to form a V as shown at ii inFig. 9, the taper being in such a direction that the mercurypassingvfrom the decomposing compartment through the passage 9 will ilowdown one of the arms of the V.

The well 'i0 forms the chamber of the brine seal, the other or outletchamber, shown at 12, (Figs. 1 and 3) being a pit located in the iioorof the oxidizing compartment. T'he bottom of the well 10 communicateswith the pit 12 through an opening or conduit 13 extending through thewall 14 that-separates the well 10 from the oxidizing compartment. It isobvious from this arrangement that a body of mercury will be maintainedin the chambers 1li and12 of the seal at a' constant level. As themercury is continuously fed into the well 10 Vit is continuouslydischarged from the pit 12 into the oxidizing compartment. The body ofmercury maintained in this manner by the seal chambers 10 and 12prevents any brine from entering the oxidizing compartment.

It will be noted that the mercury enters the well 10 in the lengthwisedirection of the well but in a direction transverse to the axis of theopening 13. The mercury thus passing into the well 10, down one side ofthe V shaped bottom and partly up its other side has its velocity spent.'I'his prevents brine from being entrained with ,the mercury as itpasses into the oxidizing compartment thus maintaining purity of thesodium hydroxide solution produced in the oxidizingicompartment. Thewell 10 also serves as a. concentration point for any broken up ordispersed mercury as well as any precipitated graphite from the mercuryfor otherwise it will pass into the oxidizing compartment through theseal and may entrain some of the brine. Furthermore, any' dispersedmercury 'which nds its way intothe oxidizing compartment will remain insuspension in the sodium hydroxide solution and 0pass off with itthereby causing a .continuous loss of mercury. The outer wall of thewell 10 has a nor- -mally closed`pipe 15 extending through it whichdroxide solution. In order -to prevent entrainment of caustic bythehydrogen gasV thus liberated, an oil layer 18 (Fig. 3) is formed byiioating on the surface' of the caustic liquor an oil which iscompletely inert toward the caustic. Prevention of entraininent oi'caustic by the hydrogen gas which is 'liberated tothe' cell room.

atmosphere .is an important consideration from a'.v health standpoint.It also decreases the loss of caustic.

Itis important to concen- In passing from `the oxidizing compartmentinto the 'pump well, the mercury forms a second seal called the causticseal because it prevents caustic from passing along with the mercury tothe pump well. I'his seal comprises a pit 11 molded in the concretefloor of the oxidizing compartment and a pit 18 molded in the concreteiioor of the pump well (Figs. 3 .and 5). Communication between these twopits is established by a passage 19 in the wall 80 which separates theoxidizing compartment from the pump well. 'I'he body of mercurymaintained in the chambers 11 and 18 at a constant level constitutes aseal similar to the one previously described. As the mercury iscontinuously fed into the compartment 11 it is continuously dischargedfrom the compartment 18 into the well of the mercury pump but no causticcan pass into the pump weil.

As previously stated the rotary mercury pump 2li picks up the mercury inthe pump well and also the water which has been fed to the pump well bythe water bucket 3l already described. The mercury and water, dischargedthrough the lateral openings 23`in the side wall of the pump, falls intoa transverse trough 8| (Figs. 1, 3, 5, and 7), which conducts them to athird mercury seal called the water seal because it prevents the waterfrom passing along with the mercury into the decomposing compartment.This seal is formed by pits 82 and 83 molded in the concrete and aconnecting passage 84 which places the bottom of these pits incommunication (Figs. l, 3, 4, 5, 6, and 7). As the mercury iscontinuously fed into the pit 82it is continuously discharged over theedge 85 of the pit 83 (Fig. 6) and then passes into the transversepassage 8 which conducts the mercury to the first channel 45 of thedecomposing compartment. The water held back by the seal 82--83-84 andwhich floats on top of the mercury as it passes through the trough 8| isconducted through a short passage 85 and discharged directly into theoxidizing compartmen (Figs. 1 and 8).

'Ihe trough 8| is so arranged as to minimize splash oi' the mercury asit is discharged from the pump 20. Splashing of the mercury at thispoint would be harmful as it would cause breaking up or dispersing ofthe mercury or would also augment vaporization. Prevention ofvaporization ot the mercury is very important from a health standpoint.A spill plate 81 (Figs. 1 and 3) extends from the bottom oi.' the trough8 I to a point closely adiacent the dischargey outlets 23 of the pump toprevent spill of the mercury back into the pump well. The water in thetrough 8| (supplied by the .oscillating bucket 3l to the pump well anddelivered by the pump to the trough 8|) acts as a'cushion for thefalling mercury. It also acts as a wash and a' submerging cover for themercury during its .travel to the water seal As previously described theoscillating water bucket 8| suppliesv a. uniform and measured quantityci' water to the oxidizing compartment. As

the water is first delivered to the pump well it 1936; Serial No.86,725, led June 23.1938; Serial cury pumpfor lifting the mercury fromthe oxidizing compartment to the decomposingv compart-v ment, a waterfeeding device discharging into the Well of the mercury pump, and meansfor separating the water from the mercury and delivering it to theoxidizing compartment after the mercury and water have been pumped andbefore the mercury is delivered to the decomposing compartment.

3. An electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, and athird compartment which receives the mercury from the oxidizingcompartment and from which it is delivered to the decomposingcompartment,

means for delivering water to the mercury while it is in said thirdcompartment, a mercury seal adapted to be traversed bythe mercury beforeit enters the decomposing compartment to prevent the water from enteringthe decomposing compartment, and means for delivering the water to theoxidizing compartment.

d. An electrolytic cell having a decomposing Acompartiment and i anoxidizing compartment throughwhich mercury may be circulated, said cellhaving a well located between the decomposing compartment and theomdizing compartment and through which the mercury is adapted to passafter it leaves the decomposing compartment and before it enters theoxidizing compartment, said well constituting one member of a mercuryseal', the other member of the seal comprising a chamber communicatingwith the oxidizing compart- -through which mercury maybe circulated andmeans for causing flow of the mercury through the decomposingcompartment in a tortuous path in one undivided continuous stream, theiioor of the decomposing compartment being provided with a plurality ofdrops over which the mercury is caused to ow during its travel in saidtortuous path.

6. iin-electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, `the oorof the decomposing compartment having a Y plurality of channelsconnected to cause the mercury to iiow through them. in one continuousundivided stream and in opposite directions in adjacent channels, saidchannels being at successively lower levels and the floor of thedecomposing compartment being provided with a drop vat the end of eachchannel over which the mercury is caused'to flow to thenext lower level.

7. An electrolytic cellvhaving a decomposing compartment and anoxidizing compartment through which mercury may be circulated, thedecomposing compartment being provided with a plurality of longitudinalpartitions forming a plurality of channels connected to cause themercury to ow through them in one continuous undivided stream and inopposite directions in adjacent channels, said channels being atsuccessively lower levels and the floor of the decomposing i compartmentbeing provided with a drop at the end of each longitudinal channel overwhich the mercury is caused to flow to the level of the next channel.'

8. An electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, and athird compartment which receives the mercury from the oxidizingcompartment and from which it is delivered to the decomposingcompartment, means in said third compartment for circulating themercury, and a water feeding device discharginginto said thirdcompartment.

9. An electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, means forconveying the mercury from the oxidizing compartment to the decomposingcompartment, and means for adding water to the mercury .while in theconveying means whereby the mercury will be covered by a layer of waterduring its transit from the oxidizing compartment to the decomposingcompartment.

10. An electrolytic cell having a decomposing l compartment and anoxidizing compartment through which mercury may be circulated, and athird compartment which receives the mercury into said thirdcompartment, and means for des livering the Water to the oxidizingcompartment and for delivering the mercury to the decompos ingcompartment.

11. An electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, and athird compartment which receives the mercury from the oxidizingcompartment and from which it is delivered to the decomposingcompartment, means in said third compartment for circulating themercury, means for admitting water to said third compartment, and amercury seal adapted to be traversed by the mercury before it enters thedecomposing compartment to prevent Athe water admitted to the thirdcompartment from entering the decomposing compartment.

v12. Ameiectrolytic cell having a decomposing iompartment and anoxidizing compartment through which mercury may be circulated, and athird compartment which receives the mercury from the oxidizingcompartmentand from which it is delivered to the decomposingcompartment. means for admitting water to said third compartment, and amercury seal adapted to be traversed by the mercury rbefore it entersthedecomposing compartment to prevent the water admittedto the thirdcompartment from entering the decomposing compartment.

13. An electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, a mercuryseal adapted to be traversed bythe mercury in passing from thedecomposing compartment to the oxidizing compartment, said sealcomprising an inlet chamber to receive mercury trom the decomposingcompartment, an outlet chamber to deliver the mercury to the oxidizingcompartment and a conduit connecting the lower portion of the twochambers, the bottom of the inlet chamber being shaped to provide a pairoiv downwardly sloping surfaces converging at said conduit, and the cellhaving a passage to conduct the mercury from the decomposing compartmentand deliver it at the upper terminus of one of said sloping surfaces,the axis of said conduit being at right angles to the direction in whichthe mercury ows down said sloping surface.

14. An electrolytic cell having a decomposing compartment and anoxidizing compartment through which mercury may be circulated, said cellhaving a Well interposed between the dccomf posing compartment and theAoxidizing compartment through which the mercury is adapted to passbefore it enters the oxidizing compartment, a conduit communicating withthe lower portion of thewell through which the mercury may pass into theoxidizing compartment, the bottom of said well being shaped to provide apair of downwardly sloping surfaces converging at said conduit, and thecell having a passage to, conduct the mercury from the decomposingcompartment and deliver it at the upper terminus of one of said slopingsurfaces, the axis of said conduit being at right angles to thedirection in which the mercury iows down said sloping surface.

15. An electrolytic cell in accordance with claim. i4 in which said wellconstitutes one chamber of a mercury seal, the second chamber of saidseal being a, pit in the iioorof the oxidizing compartment and whichcommunicates with said well through said conduit near the bottom of theWell, said weil having a normally closed outlet in its outervwalllocated above the normal level of the mercury therein through which washwater may be discharged when the cell is being cleaned.

EINAR SORENSEN.

